This map looks back in time.
Astronomers working on the Sloan Digital Sky Survey, a decades-long project to map the universe, recently released a new 3D map of the cosmos. It spans 11 billion years (out of 13.8 billion) of the history of the universe.
More than 100 scientists mapped the distances of more than two million galaxies and quasars (supermassive black holes that release enormous amounts of energy) to create a map of the universe, relative to Earth.
“We are located in the center of this map,” the group wrote, referring to the following map.
“As we look into the distance, we look back in time,” they add. (Here, we are seeing a “cut” through a sphere).
The light we see from other stars and galaxies takes a long, long time to reach Earth (for example, the light from the Andromeda galaxy takes about 2.5 million years to reach us).
The SDSS map of the universe.
Image: Anand Raichoor (EPFL) / Ashley Ross (Ohio State University) / SDSS Collaboration
The map shows different objects in space, such as galaxies, at different distances from us. In each designated colored area on the map, astronomers measure the light pattern detected by objects, all of which drift away from our galaxy as the universe expands endlessly. (The light from the oldest objects in the universe, for example, is stretched as these objects move away from us, changing the wavelength of light.)
These signatures help reveal where these objects are, relative to one another, in the ever-evolving and expanding universe.
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